The communications between a mobile terminal and a serving cell, such as the uplink communications from the mobile terminal to the serving cell, may sometimes affect resource utilization, throughput, latency and coverage. To enhance uplink communications improvements, the ongoing evolution of wireless communications systems such as, for example, the enhanced dedicated channel (E-DCH) in cell Forward Access Channel (FACH) (CELL_FACH) state feature was introduced into wireless standard specifications, such as the third generation partnership project (3GGP) Release 8 specifications.
Mobile terminals operating in a CELL_FACH mode may use a contention based E-DCH channel for uplink (UL) transmission rather than a traditional random access channel (RACH). The contention-based E-DCH channel allows for mobile terminals to transfer signaling and data at significantly higher data rates and for longer durations, which reduces transfer and state transition delays.
Support for concurrent deployment of transmission time interval (TTI) settings, (e.g., 2 millisecond (ms) and 10 ms), will be allowed for the common E-DCH in the CELL_FACH state. In this regard, the common E-DCH in the CELL_FACH state will support concurrent deployment of 2 ms and 10 ms TTI settings in a cell in 3GPP Rel-11. A single TTI setting, which may be determined and broadcast by a communications network, may be used by mobile terminals accessing the E-DCH in the CELL_FACH state within a particular cell. In this regard, for example, mobile terminals may utilize 2 ms TTIs and/or 10 ms TTIs in a cell. While a smaller TTI, such as the 2 ms TTI, may be more advantageous from fast scheduling and latency standpoints, a larger TTI, such as the 10 ms TTI, may be more widely utilized by mobile terminals in a cell to reliably transfer signaling and data to the network, particularly in coverage limited scenarios.
Although a mobile terminal may select a particular TTI (e.g., a 2 ms TTI or a 10 ms TTI) to utilize for traffic of a Dedicated Control Channel (DCCH)/Dedicated Traffic Channel (DTCH), a network may override or deny the selection of the mobile terminal. For example, the selection of the TTI by the mobile terminal may be denied in an instance in which the network determines that the selected TTI is unavailable for usage (e.g., the selected TTI is being utilized by other mobile terminals) or for other reasons. At present, the request for a 2 ms TTI may be overridden by a network by providing an indicator to the mobile terminal corresponding to a different resource (e.g., a 10 ms TTI). However, a drawback of this approach is that it restricts the total number of resources that may be used to 32 resources (e.g., a mixture of up to 32 10 ms or 2 ms TTI resources). For instance, this approach typically only allows the network to provide up to 32 resources to the mobile terminal for communication. However, it may beneficial to provide more than 32 resources to a mobile terminal, for instance, in overloaded cells in which the availability of some resources may be constrained.
In view of the foregoing drawbacks, a more reliable and efficient manner of overriding a selection of resources may be beneficial.